Surgeons in New York have completed the first-ever successful transplant of a pig's kidney into a human patient.
The organ was taken from a pig that was genetically engineered to grow organs that would not be rejected by humans. It began working normally after being attached to a brain-dead patient on a ventilator.
It's a major breakthrough for medical science - especially with over 90,000 Americans currently on the waiting list for a new kidney.
